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3 years ago

An atom had a mass of 43 and it also has has 21 electrons

Chemistry

1 answer:

Serga [27]3 years ago

8 0

scandium. if you look up the number of electrons thats the periodic number and it gives you the answer

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Ca(s) + O₂(g) + S(s) → CaSO4(s)

san4es73 [151]

The mass of Calcium required to complete this reaction is 4.008 g.

Law of conservation of mass states that In a closed system, mass cannot be produced or destroyed, but it can be changed from one form to another.
The mass of the chemical constituents before a chemical reaction is equal to the mass of the constituents after the reaction.
In several disciplines, including chemistry, mechanics, and fluid dynamics, the idea of mass conservation is widely applied.

In the given reaction mass of product after completion of reaction is 13.614 g that means total mass of constituents before reaction should also be 13.614.

So,

mass of Ca + mass of O₂ + mass of S = mass of CaSO4

Ca + 6.400 g + 3.206 g = 13.614 g

mass of Ca = 13.614 - 9.606 = 4.008 g

Therefore, by law of conservation of mass 4.008 g of Ca is required for the completion of the reaction.

Learn more about mass conservation here:

brainly.com/question/2030891

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5 0

1 year ago

A chemist makes up a solution by dissolving 42.0 g of Mg(NO3)2 in enough water to produce a final solution volume of 259 mL. To

Igoryamba

Answer:

The molar mass of Mg(NO₃)₂, 148.3 g/mol.

Explanation:

Step 1: Given data

Mass of Mg(NO₃)₂ (solute): 42.0 g

Volume of solution: 259 mL = 0.259 L

Step 2: Calculate the moles of solute

To calculate the moles of solute, we need to know the molar mass of Mg(NO₃)₂, 148.3 g/mol.

42.0 g × 1 mol/148.3 g = 0.283 mol

Step 3: Calculate the molarity of the solution

M = moles of solute / liters of solution

M = 0.283 mol / 0.259 L

M = 1.09 M

7 0

2 years ago

Ok this is the question i need help on first

just olya [345]

The answer to your question is green

3 0

2 years ago

What is a photon?

vlabodo [156]

Answer:

Explanation:

try it I'm 60%sur its this

8 0

2 years ago

Calculate to three significant digits the density of chlorine pentafluoride gas at exactly and exactly . You can assume chlorine

slega [8]

Answer:

Density is 6.16g/L

Explanation:

... at exactly -15°C and exactly 1atm...

Using general gas law:

PV = nRT

We can find density (Ratio of mass and volume) in an ideal gas as follows:

P/RT = n/V

To convert moles to grams we need to multiply the moles with Molar Weight, MW:

n*MW = m

n = m/MW

P/RT = m/V*MW

P*MW/RT = m/V

Where P is pressure: 1atm;

MW of chlorine pentafluoride: 130.445g/mol

R is gas constant: 0.082atmL/molK

And T is absolute temperature: -15°C+273.15 = 258.15K

Replacing:

P*MW/RT = m/V

1atm*130.445g/mol / 0.082atmL/molK*258.15K = m/V

6.16g/L = m/V

<h3>Density of the gas is 6.16g/L</h3>

7 0

2 years ago